Motor drive device, refrigeration cycle device, and refrigeration cycle system

Abstract

This motor drive device performs feedback control on a motor on the basis of a motor current which is a current flowing through the motor, and comprises: an index value calculation means for calculating, on the basis of the motor current and a control parameter for use in the feedback control, the electric power or the power of the motor as an index value for determining the presence or absence of an abnormality of the motor; and a filtering means for performing filtering process of removing a component of a normal operation state from the index value calculated by the index value calculation means to thereby extract an abnormality component; and a diagnosis means for diagnosing the abnormality or degradation of the motor on the basis of the abnormality component of the index value.

Description

Motor drive device, refrigeration cycle device, and refrigeration cycle system

[0001] The present disclosure relates to a motor drive device that controls the driving of a motor, a refrigeration cycle device, and a refrigeration cycle system.

[0002] Conventionally, a method for detecting an abnormality in a compressor bearing has been proposed in which an abnormality condition is determined to exist when the rate of change of the current for driving the compressor motor exceeds a reference value (see, for example, Patent Document 1). The method disclosed in Patent Document 1 determines whether an abnormality has occurred based on a comparison between the rate of change of the motor current and a predetermined reference value.

[0003] Japanese Patent Application Laid-Open No. 2019-218928

[0004] However, in the method disclosed in Patent Document 1, the current change rate to be determined is a value that changes depending on the operating frequency of the compressor or the current advance angle of the motor, etc. Therefore, the method disclosed in Patent Document 1 may erroneously determine that not only current changes caused by bearing abnormalities but also current changes caused by normal control of the compressor are abnormal. The method disclosed in Patent Document 1 may have insufficient accuracy in detecting abnormalities occurring in the motor.

[0005] The present disclosure has been made to solve the above-mentioned problems, and provides a motor drive device, a refrigeration cycle device, and a refrigeration cycle system that accurately detect an abnormal state of a motor.

[0006] The motor drive device according to the present disclosure is a motor drive device that performs feedback control of a motor based on a motor current, which is a current flowing through the motor, and includes: index value calculation means that calculates the power or power of the motor as an index value for determining whether or not there is an abnormality in the motor based on the motor current and control parameters used for the feedback control; filter means that performs filtering to remove components of a normal operating state from the index value calculated by the index value calculation means and extract abnormal components; and diagnosis means that diagnoses abnormalities or deterioration of the motor based on the abnormal components of the index value.

[0007] A refrigeration cycle device according to the present disclosure includes a refrigerant circuit including a compressor equipped with a motor, and the motor drive device described above that drives the motor.

[0008] The refrigeration cycle system according to the present disclosure comprises a refrigerant circuit having a compressor equipped with a motor, a power converter having an inverter that supplies power to the motor, a voltage command calculation means that performs feedback control of the motor via the inverter based on a motor current that is a current flowing through the motor, an index value calculation means that calculates the power or power of the motor as an index value for determining whether or not there is an abnormality in the motor based on the motor current and a control parameter used for the feedback control, a filter means that performs filtering processing to remove components of a normal operating state from the index value calculated by the index value calculation means and extract abnormal components, and a diagnosis means that diagnoses abnormalities or deterioration of the motor based on the abnormal component of the index value.

[0009] According to the present disclosure, motor abnormalities or deterioration are diagnosed based on the abnormal component obtained after removing the component representing the normal operation state of the motor from the motor's power or power as an index value indicating an abnormality occurring in the motor. Because changes related to motor control are removed from the motor's monitored value, it is possible to quantitatively determine the presence or absence of a motor abnormality and the degree of deterioration. As a result, the abnormal state of the motor can be detected with high accuracy.

[0010] 1. A diagram showing an example of the configuration of a refrigeration cycle apparatus having a motor drive device according to embodiment 1. A diagram showing an example of the configuration of a power converter shown in FIG. 1. A structural schematic diagram showing an example of the configuration of a compressor provided in the refrigeration cycle apparatus according to embodiment 1. A functional block diagram showing an example of the configuration of a controller provided in the motor drive device according to embodiment 1. A diagram showing an example of a current waveform when an abnormality occurs in the motor. A functional block diagram of the abnormality index value extraction means shown in FIG. 4. A hardware configuration diagram showing an example of the configuration of the controller shown in FIG. 4. A hardware configuration diagram showing another example of the configuration of the controller shown in FIG. 4. A block diagram showing an example of the configuration of a remote controller. A flowchart showing the procedure of an abnormal power amount extraction method according to embodiment 1. A diagram showing an example of the processing results of steps S101 to S103 shown in FIG. 10. A functional block diagram showing another example of the configuration of the abnormality index value extraction means provided in the motor drive device according to embodiment 1. A functional block diagram showing an example of the configuration of a controller provided in the motor drive device according to embodiment 2. A functional block diagram of the abnormality index value extraction means shown in FIG. 13. A diagram showing an example of the configuration of a refrigeration cycle system having the refrigeration cycle apparatus according to embodiment 1.

[0011] Embodiment 1. The configuration of a motor drive device according to this embodiment 1 will be described. Fig. 1 is a diagram showing an example of the configuration of a refrigeration cycle device having a motor drive device according to embodiment 1. As shown in Fig. 1, a refrigeration cycle device 100 has a heat source unit 101, a load unit 102, and a remote controller 9.

[0012] The heat source side unit 101 has a compressor 1, a heat source side heat exchanger 2, a throttling device 3, a four-way valve 5, and an accumulator 6. The load side unit 102 has a load side heat exchanger 4. The compressor 1, the heat source side heat exchanger 2, the throttling device 3, and the load side heat exchanger 4 are connected by refrigerant piping 7 to form a refrigerant circuit 10 in which the refrigerant circulates. In the first embodiment, the refrigeration cycle apparatus 100 will be described as an air conditioner, but the refrigeration cycle apparatus 100 is not limited to an air conditioner.

[0013] The compressor 1 draws in gas refrigerant, compresses it, and discharges it. The compressor 1 is an inverter compressor with a variable capacity. The throttling device 3 decompresses and expands the refrigerant. The heat source side heat exchanger 2 and the load side heat exchanger 4 are heat exchangers that exchange heat between the refrigerant and air. The heat source side heat exchanger 2 and the load side heat exchanger 4 are, for example, fin-and-tube heat exchangers. The four-way valve 5 switches the flow direction of the refrigerant circulating through the refrigerant circuit 10 according to the operation mode of the refrigeration cycle apparatus 100. The four-way valve 5 allows the refrigerant discharged from the compressor 1 to flow into the load side heat exchanger 4 when the operation mode is heating operation, and allows the refrigerant discharged from the compressor 1 to flow into the heat source side heat exchanger 2 when the operation mode is cooling operation. The accumulator 6 is connected to the refrigerant suction port side of the compressor 1. The accumulator 6 is a refrigerant circuit accessory that prevents liquid refrigerant from being drawn into the compressor 1.

[0014] The heat source unit 101 also has a control device 8 that controls the refrigeration cycle of the refrigerant circulating through the refrigerant circuit 10, and a motor drive device 15 that drives the compressor 1. The motor drive device 15 is connected via wiring to a motor 12 mounted on the compressor 1. The motor 12 is, for example, a three-phase brushless DC motor. The motor drive device 15 has a power converter 21 that supplies power to the motor 12 via wiring, a current sensor 22 that detects the motor current that flows through the motor 12, and a controller 23 that controls the drive of the motor 12. The current sensor 22 is provided on the wiring that connects the power converter 21 and the motor 12.

[0015] The control device 8 is connected to the expansion device 3, the four-way valve 5, the controller 23, and the remote controller 9 via signal lines (not shown). The remote controller 9 allows a user of the refrigeration cycle apparatus 100 to input, to the control device 8, the operation mode of the refrigeration cycle apparatus 100, the set temperature of the space to be air-conditioned in the load side unit 102, and the like. The control device 8 controls the four-way valve 5, the expansion device 3, and the compressor 1 in accordance with instructions regarding the operation mode and the like input by the user via the remote controller 9. With respect to the compressor 1, specifically, the control device 8 determines a speed command value ω* corresponding to the operation frequency of the motor 12 in accordance with the instructions input by the user, and transmits the speed command value ω* to the controller 23.

[0016] Fig. 2 is a diagram showing an example of the configuration of the power converter shown in Fig. 1. Power converter 21 has DC voltage source 13 and inverter 20. Inverter 20 has a plurality of switching elements 71a to 73a and 71b to 73b.

[0017] A switching element 71a is provided in the upper arm of the U phase, and a switching element 71b is provided in the lower arm of the U phase. A switching element 72a is provided in the upper arm of the V phase, and a switching element 72b is provided in the lower arm of the V phase. A switching element 73a is provided in the upper arm of the W phase, and a switching element 73b is provided in the lower arm of the W phase. A DC voltage output from DC voltage source 13 is applied between the upper and lower arms of each of the U, V, and W phases, and the connection points of the upper and lower arms of each phase are wired to motor 12.

[0018] Each of switching elements 71a to 73a and 71b to 73b of inverter 20 performs a switching operation in response to a control signal input from voltage command calculation means 24. Power converter 21 switches the output from DC voltage source 13 to apply an AC voltage of a given frequency to motor 12 to drive motor 12.

[0019] Next, a structure of the compressor 1 will be described. In the first embodiment, the compressor 1 will be described as a scroll compressor, but the type of the compressor 1 is not limited to a scroll compressor. Fig. 3 is a structural schematic diagram showing an example of the configuration of a compressor provided in the refrigeration cycle apparatus according to the first embodiment.

[0020] 3, compressor 1 has a compression mechanism consisting of fixed scroll 40 and orbiting scroll 41, motor 12 equipped with main shaft 45 as a rotation shaft, suction pipe 47, discharge pipe 49, and oil pump 54. The compression mechanism, motor 12, and oil pump 54 are housed in a cylindrical sealed container 52.

[0021] The motor 12 has a main shaft 45, a stator 43, and a rotor 44. The main shaft 45 is attached to the rotor 44. The main shaft 45 is supported by two bearings: a main bearing 50 and an auxiliary bearing 51. Specifically, the upper side of the main shaft 45 is supported by the main bearing 50, which is a plain bearing, and the lower side is supported by the auxiliary bearing 51, which is a ball bearing. Because the refrigerant circuit 10 needs to be sealed to transport the refrigerant, the compression mechanism, bearings, motor 12, and other rotating members are all placed in an environment where they are exposed to the refrigerant.

[0022] The suction pipe 47 is provided on the side surface of the sealed container 52 and draws in the gas refrigerant from the accumulator 6. The discharge pipe 49 is provided on the top surface of the sealed container 52 and discharges the gas refrigerant compressed by the compression mechanism to the four-way valve 5. A power supply terminal 42 is provided on the side surface of the sealed container 52 for connecting wiring extending from the inverter 20 to the windings of the motor 12. The oil pump 54 sucks up lubricating oil that accumulates at the bottom of the sealed container 52 and sends it to sliding parts including the compression mechanism and bearings.

[0023] In the compression mechanism, the fixed scroll 40 and the orbiting scroll 41 are arranged so that the fixed scroll provided below the fixed scroll 40 and the orbiting scroll provided above the orbiting scroll 41 mesh with each other. A main shaft eccentric portion 46 is provided above the main shaft 45. The orbiting scroll 41 is attached to the main shaft 45 via the main shaft eccentric portion 46. A discharge port 48 is provided above the fixed scroll 40 to allow the compressed gas refrigerant to flow toward a discharge pipe 49.

[0024] The compressor 1 compresses the gas refrigerant by orbiting the orbiting scroll 41 using rotational power generated by the motor 12. The gas refrigerant is drawn into the compressor 1 through a suction pipe 47, compressed by the orbiting movement of the orbiting scroll 41, and then discharged from a discharge pipe 49.

[0025] Next, the configuration of the controller 23 will be described. Fig. 4 is a functional block diagram showing an example of the configuration of the controller provided in the motor drive device according to embodiment 1. The controller 23 is, for example, a microcomputer. As shown in Fig. 4, the controller 23 has a voltage command calculation means 24 and an abnormality index value extraction means 25.

[0026] Power converter 21 is connected to windings of each of the U, V, and W phases of motor 12. Voltage command calculation means 24 performs feedback control of motor 12 via inverter 20 shown in Fig. 2 based on the motor current. Voltage command calculation means 24 has a speed control unit 30, a current control unit 31, a first coordinate conversion unit 32, a second coordinate conversion unit 33, and a position / speed estimator 34. Fig. 4 shows a case where the number of magnetic poles of the permanent magnet of rotor 44 of motor 12 is six, but the number of magnetic poles is not limited to six.

[0027] Since the motor 12 of the compressor 1 is housed inside the sealed container 52, which is subject to high temperature and pressure, it is difficult to provide a sensor for detecting the rotational position of the rotor 44 inside the sealed container 52. Therefore, the voltage command calculation means 24 performs position sensorless control on the motor 12 via the inverter 20 based on the motor current. The voltage command calculation means 24 shown in Fig. 4 is an example of a configuration in which the motor 12 is driven by position sensorless vector control.

[0028] The current sensor 22 serves to detect values ​​for estimating the drive state of the motor 12 and the operating state of the compressor 1. The current sensor 22 detects a U-phase motor current iu and a W-phase motor current iw of the motor 12 and transmits the motor currents iu and iw to the second coordinate conversion unit 33. In the first embodiment, the current sensor 22 detects the motor currents iu and iw, but is not limited to these two current values. The current values ​​detected by the current sensor 22 may be a combination of any two of the motor current iu, motor current iw, and V-phase motor current iv, or may be all three of these current values.

[0029] The second coordinate converter 33 receives a phase θ indicating the estimated position from the position / speed estimator 34 and receives motor currents iu and iw from the current sensor 22. The phase θ is an estimated relative angle of the rotor 44 with respect to the stator 43 and indicates the estimated position of the rotor 44 relative to a reference position. The second coordinate converter 33 calculates the motor current iv from the equation iu + iv + iw = 0 and the motor currents iu and iw. The second coordinate converter 33 coordinate-transforms the motor currents iu, iv, and iw while referring to the phase θ to determine the d-axis current Id and the q-axis current Iq. The second coordinate converter 33 transmits the d-axis current Id and the q-axis current Iq to the current controller 31, the position / speed estimator 34, and the abnormality index value extractor 25. The d-axis current Id and the q-axis current Iq are examples of control parameters used in feedback control.

[0030] The speed control unit 30 calculates an excitation current command value Id* and a torque current command value Iq* based on the speed command value ω* and the estimated speed ω^ received from the position and speed estimator 34 so that the speed converges to the speed command value ω*. The speed control unit 30 transmits the excitation current command value Id* and the torque current command value Iq* to the current control unit 31. The excitation current command value Id* and the torque current command value Iq* are examples of control parameters used in feedback control.

[0031] The current control unit 31 determines voltage command values ​​Vd* and Vq* based on the d-axis current Id and q-axis current Iq received from the second coordinate conversion unit 33 and the excitation current command value Id* and torque current command value Iq* received from the speed control unit 30 so that the currents converge to the current command values. The current control unit 31 transmits the voltage command values ​​Vd* and Vq* to the first coordinate conversion unit 32, the position / speed estimator 34, and the abnormality index value extracting means 25. The voltage command values ​​Vd* and Vq* are examples of control parameters used in feedback control.

[0032] The position and speed estimator 34 uses the d-axis current Id and q-axis current Iq received from the second coordinate converter 33 and the voltage command values ​​Vd* and Vq* received from the current controller 31 to determine a phase θ indicating an estimated position of the rotor 44 of the motor 12 and an estimated speed ω^. The position and speed estimator 34 transmits the phase θ indicating the estimated position to the first coordinate converter 32 and the second coordinate converter 33. The position and speed estimator 34 transmits the estimated speed ω^ to the speed controller 30. The phase θ indicating the estimated position of the rotor 44 and the estimated speed ω^ are examples of control parameters used in feedback control.

[0033] First coordinate transformation unit 32 receives phase θ from position / speed estimator 34 and voltage command values ​​Vd* and Vq* from current control unit 31, and then performs coordinate transformation on the received voltage command values ​​Vd* and Vq* to determine voltage command values ​​Vu*, Vv*, and Vw*. First coordinate transformation unit 32 transmits voltage command values ​​Vu*, Vv*, and Vw*, which are control signals for inverter 20, to power converter 21 while referring to the phase θ. Voltage command values ​​Vu*, Vv*, and Vw* are examples of control parameters used in feedback control.

[0034] The voltage command calculation means 24 repeatedly performs the above calculations, thereby controlling the motor 12 so that the rotation speed coincides with the speed command value ω*.

[0035] Next, before describing the configuration of the abnormality index value extraction means 25 of the first embodiment, we will explain the principle of the abnormal power amount extraction method by the abnormality index value extraction means 25. First, we will explain the case where the compressor 1 is rotating and operating at a constant operating frequency in a normal state.

[0036] The load torque applied to the rotating shaft of the motor 12 of the compressor 1 is divided into a component that depends on the compression of the gas refrigerant and a component that depends on the pressure of the gas refrigerant. Hereinafter, the compression of the gas refrigerant will be referred to as gas compression, and the pressure of the gas refrigerant will be referred to as gas pressure.

[0037] The torque component dependent on gas compression is due to a series of operations performed during one rotation of the compressor 1 and is characterized by a pulsating waveform containing components multiplied by the rotational frequency. The series of operations refers to the sequential intake, compression, and discharge of refrigerant gas. Because the rotational speed of the compressor 1 is often in the range of 30 to 120 rps, the pulsating waveform generally contains frequency components of 30 Hz or higher. In other words, the pulsating waveform contains harmonics, which are integer multiples of the rotational frequency of the compressor 1 as a fundamental wave. Meanwhile, gas pressure varies depending on room temperature, outside temperature, and the aperture of the throttle device 3, but changes in gas pressure due to these factors change slowly, with a response time of several tens of seconds. Therefore, the torque waveform due to gas pressure is characterized by DC and extremely low frequency components.

[0038] Next, we will explain how an abnormality occurring in the refrigerant circuit 10 can cause deterioration or malfunction in the compressor 1. The refrigerant circuit 10 contains parts that are continuously subjected to mechanical stress, such as pipe joints and moving parts of valves. This stress can cause pieces of refrigerant equipment components to peel off. The peeled off pieces circulate through the refrigerant circuit 10 with the flow of refrigerant, but because the refrigerant circuit 10 is a closed circuit, the pieces are not expelled and can act as foreign matter, causing continuous deterioration of the compressor 1.

[0039] Furthermore, foreign matter may be generated not only at the joints of the refrigerant pipes 7 and the moving parts of the valves, but also inside the compressor 1. Lubricating oil pumped up by the oil pump 54 is normally supplied to the sliding parts inside the compressor 1, such as the main bearing 50. However, if the oil concentration decreases due to some influence, poor lubrication occurs, resulting in direct contact between metals. Friction at this time causes oxidation of the oil or peeling at the interface, which becomes foreign matter. For example, a peeled portion of a bearing becomes foreign matter.

[0040] FIG. 5 is a diagram showing an example of a current waveform when an abnormality occurs in the motor. FIG. 5 is an example of a current waveform detected when a foreign object is generated inside the compressor 1 due to metal-to-metal contact. The vertical axis of the graph shown in FIG. 5 represents the current flowing through the motor 12. The horizontal axis of the graph shown in FIG. 5 represents the elapsed time t from a reference time. FIG. 5 shows, in chronological order, the current flowing through the motor 12 for each rotation of the motor 12. Specifically, FIG. 5 shows the current waveform of the motor 12 when the motor 12 rotates four times in the order of a first rotation period T1 to a fourth rotation period T4 from a reference time where the elapsed time t=0.

[0041] The solid lines indicate the current waveforms of the motor 12 in the first rotation period T1 to the fourth rotation period T4, and the dashed lines indicate the current waveforms in the third rotation period T3 to the fourth rotation period T4 when no abnormality occurs in the motor 12. With reference to the third rotation period T3 to the fourth rotation period T4, the current indicated by the solid lines becomes larger than the current waveform indicated by the dashed lines at elapsed time tx1, and returns to the current waveform indicated by the dashed lines at elapsed time tx2.

[0042] When foreign matter generated by metal-to-metal contact gets caught in the bearings of the compressor 1 or in the seals of the compression mechanism, the load torque increases and the current waveform temporarily increases until the trapped foreign matter passes through or is crushed. The current waveform from elapsed time tx1 to tx2 shown in Figure 5 shows the temporary increase in the current waveform caused by the foreign matter. The passing of foreign matter or the crushing of foreign matter occurs randomly, and the magnitude of the load torque and the timing of its occurrence are also irregular.

[0043] As described above, the load torque due to a foreign object has different characteristics from the load torque due to gas compression and gas pressure. That is, the torque due to a foreign object is the component remaining after separating the torque component due to gas compression, which occurs regularly, from the load torque of the motor 12 and the torque component due to slowly changing gas pressure. Hereinafter, the torque due to a foreign object is referred to as abnormal torque.

[0044] The degree of deterioration of the sliding parts of the compressor 1 is considered to be proportional to the magnitude of work caused by abnormal torque. Generally, the work of a rotating body is defined by the formula "torque x rotational speed x time." Therefore, the abnormal work, which is the work caused by the abnormal torque, can be calculated by the formula "abnormal torque x rotational speed x time." Furthermore, from an electrical perspective, work is synonymous with the amount of power. Therefore, the degree of deterioration of the sliding parts of the compressor 1 can also be calculated by the formula "abnormal power x time." Abnormal power is the value obtained by removing the power component when the compressor 1 is operating normally from the power of the motor 12. Hereinafter, the value calculated by the formula "abnormal power x time" will be referred to as the amount of abnormal power.

[0045] Based on the above-described principle, the abnormal work or abnormal power amount can be obtained using the power or power rate of the motor 12 as an index value for determining whether or not there is an abnormality in the motor 12, thereby making it possible to quantitatively observe the deterioration state of the compressor 1 equipped with the motor 12. In the present embodiment 1, a case will be described in which the abnormality index value extraction means 25 obtains the abnormal power amount.

[0046] The configuration of the abnormality index value extraction means 25 shown in Fig. 4 will be described. Fig. 6 is a functional block diagram of the abnormality index value extraction means shown in Fig. 4. The abnormality index value extraction means 25 has index value calculation means 60, filter means 61, and integration means 62. Fig. 6 shows an example of the configuration when the abnormality index value extraction means 25 integrates abnormal power changes that occur during constant speed operation of the motor 12.

[0047] The index value calculation means 60 receives the voltage command value Vd* and the voltage command value Vq* sequentially from the current control unit 31, and receives the d-axis current Id and the q-axis current Iq sequentially from the second coordinate conversion unit 33. The index value calculation means 60 calculates the inner product of the voltage command value Vd* and the d-axis current Id, calculates the inner product of the voltage command value Vq* and the q-axis current Iq, and calculates the sum of these inner products as the instantaneous power P. The index value calculation means 60 transmits the calculated instantaneous power P to the filter means 61.

[0048] The speed command value ω* is input to the filter means 61. The filter means 61 has a low-pass filter (LPF) 63 and a high-pass filter (HPF) 64. The LPF 63 removes harmonic components having a fundamental wave corresponding to the rotational frequency of the motor 12 in a normal operating state from the instantaneous power P. This attenuates, of the instantaneous power P, torque fluctuations that occur when the compressor 1 performs a compression operation in a normal operating state. The HPF 64 removes, from the instantaneous power P, low-frequency components that occur in a normal operating state of the motor 12. This attenuates, of the instantaneous power P, low-frequency components that are work components due to gas pressure.

[0049] Furthermore, the filter means 61 monitors whether or not the input speed command value ω* changes, and if the speed command value ω* changes, removes the power change corresponding to the change in the speed command value ω* from the instantaneous power P. Through the calculation process by the filter means 61, power changes due to normal operating conditions are removed from the instantaneous power P, and only the abnormal power component Psg is output from the filter means 61. In this way, the filter means 61 receives the instantaneous power P as input, performs filtering to remove components due to the normal operating conditions of the compressor 1 from the instantaneous power P, and extracts the abnormal power component Psg.

[0050] When the anomalous power component Psg is input from the filter means 61, the integrator means 62 calculates the anomalous power amount Psgh by time-integrating the power component Psg. The integrator means 62 transmits the anomalous information Wir, which is information indicating the anomalous power amount Psgh, to the diagnostic means 35 at regular intervals.

[0051] Here, an example of hardware of the controller 23 shown in Fig. 4 will be described. Fig. 7 is a hardware configuration diagram showing an example of the configuration of the controller shown in Fig. 4. When the various functions of the controller 23 are executed by hardware, the controller 23 shown in Fig. 4 is configured by a processing circuit 80 as shown in Fig. 7. The functions of the voltage command calculation means 24 and the abnormality index value extraction means 25 shown in Fig. 4 are realized by the processing circuit 80.

[0052] When each function is performed by hardware, the processing circuit 80 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. The functions of each means of the voltage command calculation means 24 and the abnormality index value extraction means 25 may be realized by the processing circuit 80 individually. Furthermore, the functions of each means of the voltage command calculation means 24 and the abnormality index value extraction means 25 may be realized by a single processing circuit 80.

[0053] Another example of hardware for the controller 23 shown in Fig. 4 will now be described. Fig. 8 is a hardware configuration diagram showing another example of the configuration of the controller shown in Fig. 4. When the various functions of the controller 23 are executed by software, the controller 23 shown in Fig. 4 has a processor 81 such as a CPU (Central Processing Unit) and a memory 82, as shown in Fig. 8. The functions of the voltage command calculation means 24 and the abnormality index value extraction means 25 are realized by the processor 81 and the memory 82. Fig. 8 shows that the processor 81 and the memory 82 are communicably connected to each other via a bus 83.

[0054] When each function is performed by software, the functions of the voltage command calculation means 24 and the abnormality index value extraction means 25 are realized by software, firmware, or a combination of software and firmware. The software and firmware are written as programs and stored in the memory 82. The processor 81 realizes the functions of each means by reading and executing the programs stored in the memory 82.

[0055] The memory 82 may be a non-volatile semiconductor memory such as a read-only memory (ROM), a flash memory, an erasable and programmable ROM (EPROM), or an electrically erasable and programmable ROM (EEPROM). Alternatively, a volatile semiconductor memory such as a random access memory (RAM) may be used as the memory 82. Alternatively, the memory 82 may be a removable recording medium such as a magnetic disk, a flexible disk, an optical disk, a compact disc (CD), a mini disc (MD), or a digital versatile disc (DVD).

[0056] Next, the configuration of the remote controller 9 will be described. Fig. 9 is a block diagram showing an example of the configuration of the remote controller. The remote controller 9 has an operation unit 75 such as a touch panel, a display unit 76 such as a liquid crystal display, and a control unit 77. The control unit 77 has diagnostic means 35. The hardware configuration of the control unit 77 is similar to the configuration described with reference to Figs. 7 and 8, so a detailed description thereof will be omitted.

[0057] When the diagnostic means 35 receives the abnormality information Wir from the abnormality index value extracting means 25, it determines whether the abnormal power amount Psgh, which is the integrated value of the calculation result by the integrating means 62, is greater than a predetermined first threshold value th1. If the abnormal power amount Psgh is greater than the first threshold value th1, the diagnostic means 35 determines whether the amount of change in the abnormal power amount Psgh per unit time is greater than a predetermined second threshold value th2. If the amount of change in the abnormal power amount Psgh is greater than the second threshold value th2, the diagnostic means 35 causes the display unit 76 to display information that the abnormal power amount Psgh has exceeded the second threshold value th2.

[0058] Furthermore, upon receiving the abnormality information Wir from the abnormality index value extraction means 25, the diagnostic means 35 may cause the display unit 76 to display the abnormal power amount Psgh regardless of whether the abnormal power amount Psgh is greater than the first threshold value th1. Furthermore, if the abnormal power amount Psgh is greater than the first threshold value th1, the diagnostic means 35 may cause the display unit 76 to display information indicating that the abnormal power amount Psgh is greater than the first threshold value th1. If the abnormal power amount Psgh is greater than the first threshold value th1, the diagnostic means 35 may diagnose that an abnormality has occurred in the motor 12 or that the motor 12 has deteriorated, and display information indicating that an abnormality has occurred in the motor 12 or that the motor 12 has deteriorated as a diagnostic result on the display unit 76. If the remote controller 9 is provided with an audio output device (not shown), the diagnostic means 35 may output the diagnostic result to the audio output device. In this case, the audio output device (not shown) outputs the diagnostic result information via a speaker (not shown).

[0059] In the first embodiment, the case where the diagnostic means 35 is provided in the remote controller 9 has been described, but the electronic device in which the diagnostic means 35 is provided is not limited to the remote controller 9. The diagnostic means 35 may be provided in the controller 23. In addition, the destination of the abnormality information Wir including the calculation result output from the integration means 62 to the outside is not limited to the diagnostic means 35.

[0060] For example, if the refrigeration cycle apparatus 100 is provided with a display device (not shown), the integrating means 62 may output the abnormality information Wir to the display device and cause the display device to display the abnormal power amount Psgh. Also, if the refrigeration cycle apparatus 100 is provided with an audio output device (not shown), the integrating means 62 may output the abnormality information Wir to the audio output device. In this case, the audio output device (not shown) outputs the value of the abnormal power amount Psgh indicated by the abnormality information Wir via a speaker (not shown).

[0061] Next, a description will be given of the operation of motor drive device 15 according to the first embodiment. Fig. 10 is a flowchart showing the procedure of the anomalous power amount extraction method according to the first embodiment.

[0062] First, the index value calculation means 60 calculates the dot product of the voltage command value Vd* and the d-axis current Id, calculates the dot product of the voltage command value Vq* and the q-axis current Iq, and calculates the sum of these dot products as the instantaneous power P (step S101). Next, the LPF 63 of the filter means 61 removes from the instantaneous power P harmonic components based on the rotational frequency of the motor 12 in a normal operating state. The HPF 64 removes from the instantaneous power P low-frequency components in a normal operating state of the motor 12. This attenuates the low-frequency components of the instantaneous power P that are the work components of the gas pressure, and attenuates torque fluctuations that occur when the compressor 1 performs a compression operation. In this way, the filter means 61 removes the normal operating state components from the instantaneous power P to calculate the abnormal power component Psg (step S102).

[0063] In step S102, the filter means 61 monitors whether or not the speed command value ω* changes, and if the speed command value ω* changes, removes the power change corresponding to the change in the speed command value ω* from the instantaneous power P. By performing these filtering processes, power changes due to normal operating conditions are removed from the instantaneous power P, and only the abnormal power component Psg is output from the filter means 61. In this way, by the filter means 61 performing filtering processes on the instantaneous power P, the abnormal power component Psg can be extracted from the instantaneous power P.

[0064] When the filtered power component Psg of the instantaneous power P is input from the filter means 61, the integrator 62 performs time integration on the power component Psg to calculate the anomalous power amount Psgh (step S103). The integrator 62 outputs the abnormality information Wir, which is information on the anomalous power amount Psgh, to the diagnostic means 35 (step S104).

[0065] In this way, the abnormality index value extraction means 25 calculates the abnormal power amount Psgh using the voltage command values ​​Vd* and Vq*, the d-axis current Id, and the q-axis current Iq, and provides information on the calculated abnormal power amount Psgh to the diagnostic means 35.

[0066] When the diagnostic means 35 receives the abnormality information Wir from the integrating means 62, it diagnoses the motor 12 for abnormality or degradation based on the abnormal power amount Psgh (step S105). Specifically, the diagnostic means 35 determines whether the abnormal power amount Psgh is greater than the first threshold value th1. If the abnormal power amount Psgh is greater than the first threshold value th1, it diagnoses that an abnormality or degradation has occurred in the motor 12. Then, as a diagnostic result, it causes the display unit 76 to display information indicating that an abnormality has occurred in the motor 12 or that the motor 12 has deteriorated. On the other hand, if the abnormal power amount Psgh is equal to or less than the first threshold value th1, it diagnoses that no abnormality has occurred in the motor 12 and that the motor 12 has not deteriorated. In this case, the diagnostic means 35 may, but need not, display a diagnostic result indicating that no abnormality has occurred in the motor 12 on the display unit 76.

[0067] Fig. 11 is a diagram showing an example of the processing results of steps S101 to S103 shown in Fig. 10. Fig. 11 shows the current waveform shown in Fig. 5 in the top row, the instantaneous power P calculated by the index value calculation means 60 in the second row, the power component Psg calculated by the filter means 61 in the third row, and the anomalous power amount Psgh calculated by the integrating means 62 in the bottom row.

[0068] If an abnormality occurs inside the compressor 1, such as partial separation of a bearing due to a lack of lubricating oil, the current waveform of the motor 12 increases at elapsed time tx1, as shown in the top graph of Fig. 11. This current waveform is dq-transformed to obtain the d-axis current Id and the q-axis current Iq, and the dot products of the d-axis current Id and the q-axis current Iq and the voltage command values ​​Vd* and Vq* are calculated to obtain the instantaneous power P converted into a scalar quantity. The instantaneous power P begins to increase from elapsed time tx1 and suddenly drops to the level of the first rotation period T1 and the second rotation period T2 at elapsed time tx2.

[0069] Of the instantaneous power P shown in the second row of Fig. 11, the DC amount is a load component due to normal operating conditions, and the high frequency is a pulsating component due to gas compression. Therefore, when these components are removed from the instantaneous power P by the filter means 61, only the abnormal power component Psg remains, as shown in the third row of Fig. 11. After that, when the abnormal power component Psg is integrated over time by the integrator means 62, the abnormal power consumption is determined as the abnormal power amount Psgh, as shown in the bottom row of Fig. 11.

[0070] 10 , when the diagnostic means 35 receives information on the anomalous power amount Psgh from the integrating means 62, it displays the anomalous power amount Psgh on the display unit 76. In this case, the user and maintenance manager of the refrigeration cycle apparatus 100 can estimate the abnormal or deteriorated state of the motor 12 or the compressor 1 based on the value of the anomalous power amount Psgh displayed on the display unit 76.

[0071] 10 , when the diagnostic means 35 receives the abnormality information Wir from the abnormality index value extraction means 25, the diagnostic means 35 determines whether the abnormal power amount Psgh is greater than the first threshold value th1. At the elapsed time tb12 in the graph at the bottom of FIG. 11 , the abnormal power amount Psgh is greater than the first threshold value th1. If the abnormal power amount Psgh is greater than the first threshold value th1 as a result of the determination, the diagnostic means 35 displays information indicating that the abnormal power amount Psgh is greater than the first threshold value th1 on the display unit 76. In this case, the user and maintenance manager of the refrigeration cycle apparatus 100 can infer that the greater the abnormal power amount Psgh is determined to be than the first threshold value th1, the greater the degree of abnormality or deterioration occurring in the compressor 1.

[0072] 10 , if the abnormal power amount Psgh is greater than the first threshold value th1, the diagnostic means 35 determines whether the amount of change in the abnormal power amount Psgh is greater than the second threshold value th2. If the result of the determination is that the amount of change in the abnormal power amount Psgh is greater than the second threshold value th2, the diagnostic means 35 causes the display unit 76 to display information indicating that the amount of change in the abnormal power amount Psgh has exceeded the second threshold value th2. In this case, the user and maintenance manager of the refrigeration cycle apparatus 100 can estimate that the motor 12 or the compressor 1 is in an abnormal state or a deteriorated state to the extent that maintenance of the compressor 1 is required.

[0073] The diagnostic means 35 periodically monitors the amount of change in the anomalous power amount Psgh, allowing the user and maintenance manager of the refrigeration cycle apparatus 100 to know of any sudden abnormalities occurring in the compressor 1 and to determine the urgency of maintenance. The motor drive device 15 monitors the motor 12 and the compressor 1 as described above, allowing the user and maintenance manager of the refrigeration cycle apparatus 100 to prevent sudden failure of the compressor 1 due to foreign matter, etc.

[0074] In this way, the abnormality index value extraction means 25 calculates the abnormal power consumption Psgh of the motor 12, allowing the user and maintenance manager of the refrigeration cycle device 100 to estimate not only whether or not there is an abnormality in the motor 12 or the compressor 1, but also whether or not there is mechanical deterioration in the compressor 1.

[0075] In the first embodiment, diagnostic means 35 may be provided in motor drive device 15. Diagnostic means 35 may also diagnose abnormality or degradation of motor 12 based on abnormal power component Psg output from filter means 61. Fig. 12 is a functional block diagram showing another example configuration of abnormality index value extraction means provided in the motor drive device according to the first embodiment.

[0076] 12 , the abnormality index value extraction means 25a includes a diagnosis means 35. The diagnosis means 35 diagnoses abnormality or degradation of the motor 12 based on the abnormal power component Psg output from the filter means 61. Furthermore, upon receiving the abnormal power amount Psgh from the integrator means 62, the diagnosis means 35 diagnoses abnormality or degradation of the motor 12 based on the abnormal power amount Psgh. In other words, the diagnosis means 35 may diagnose abnormality or degradation of the motor 12 based on one or both of the values ​​of the abnormal power component Psg and the abnormal power amount Psgh.

[0077] An example will be described in which the motor 12 is diagnosed using one of two parameters, the abnormal power component Psg and the abnormal power amount Psgh. The diagnostic means 35 determines whether the abnormal power component Psg is greater than a predetermined abnormality determination threshold thd1. If the abnormal power component Psg is greater than the abnormality determination threshold thd1, the diagnostic means 35 diagnoses that an abnormality has occurred in the motor 12 or that the motor 12 is degraded. This has the advantage of diagnosing the abnormality or degradation of the motor 12 before calculating the abnormal power amount Psgh. The diagnostic means 35 also determines whether the abnormal power amount Psgh included in the abnormality information Wir is greater than a first threshold th1. If the abnormal power amount Psgh is greater than the first threshold th1, the diagnostic means 35 diagnoses that an abnormality has occurred in the motor 12 or that the motor 12 is degraded. In this case, even if noise occurs in the power P regardless of abnormality or deterioration of the motor 12, erroneous diagnosis due to noise can be prevented, and the condition of the motor 12 can be diagnosed more accurately using the value obtained by integrating the abnormal power component Psg over time.

[0078] Next, an example will be described in which the motor 12 is diagnosed using both of the two parameters, the abnormal power component Psg and the abnormal power amount Psgh. The diagnostic means 35 determines whether the abnormal power component Psg is greater than the abnormality determination threshold thd1. The diagnostic means 35 also determines whether the abnormal power amount Psgh is greater than the first threshold th1. If the abnormal power component Psg is greater than the abnormality determination threshold thd1 and the abnormal power amount Psgh is greater than the first threshold th1, the diagnostic means 35 diagnoses that an abnormality has occurred in the motor 12 or that the motor 12 is degraded. On the other hand, if the abnormal power amount Psgh is greater than the first threshold th1 but is equal to or less than the first threshold th1, the diagnostic means 35 diagnoses that no abnormality has occurred in the motor 12 and that the motor 12 is not degraded. In this way, by performing a diagnosis using two parameters, it is possible to prevent erroneous diagnosis due to power noise generated in the motor 12, and to more accurately diagnose the state of the motor 12 using the abnormal power amount Psgh.

[0079] If the diagnostic means 35 diagnoses that an abnormality or deterioration has occurred in the motor 12, it transmits information indicating that an abnormality or deterioration has occurred in the motor 12 to the remote controller 9 as the diagnostic result. When the remote controller 9 receives the diagnostic result from the diagnostic means 35, it displays the diagnostic result information on the display unit 76. By diagnosing the motor 12 using the abnormal power component Psg of the two parameters, it is possible to notify the user of an abnormality more quickly when an abnormality occurs in the motor 12. Furthermore, by including the abnormal power amount Psgh as a parameter used for diagnosis, it is possible to more accurately notify the user of an abnormality or deterioration that has occurred in the motor 12. While FIG. 12 illustrates a configuration in which the diagnostic means 35 is provided in the abnormality index value extraction means 25a, the diagnostic means 35 may be provided elsewhere within the motor drive device 15.

[0080] Motor drive device 15 of the first embodiment has index value calculation means 60, filter means 61, and diagnostic means 35. Index value calculation means 60 calculates electric power P of motor 12 as an index value for determining whether or not an abnormality exists in motor 12, based on the motor current, which is the current flowing through motor 12, and control parameters used for feedback control of motor 12. Filter means 61 performs filtering processing to remove normal operating state components from electric power P calculated by index value calculation means 60 and extract abnormal components. Diagnostic means 35 diagnoses abnormality or degradation of motor 12 based on the abnormal component of electric power P.

[0081] According to the first embodiment, an abnormality or deterioration of the motor 12 is diagnosed based on the abnormality component remaining after removing the component representing the normal operating state of the motor 12 from the power P of the motor 12 as an index value indicating an abnormality occurring in the motor 12. Because changes related to the control of the motor 12 are removed from the monitored value of the motor 12, it is possible to quantitatively determine whether or not there is an abnormality in the motor 12 and the degree of deterioration. As a result, it is possible to accurately detect the abnormality or deterioration state of the motor 12.

[0082] Furthermore, in the first embodiment, an abnormality or degradation of the motor 12 may be diagnosed using a value obtained by time-integrating the abnormal component after removing the component representing the normal operating state of the motor 12 from the power P of the motor 12 as an index value indicating an abnormality occurring in the motor 12. Specifically, the power P is calculated from the motor current and voltage command value, and abnormal power consumption is extracted from the power P by the filter means 61. The abnormal power consumption is then integrated to obtain diagnostic information. In this manner, changes related to the control of the motor 12 are removed from the monitored value of the motor 12, allowing the presence or absence of an abnormality and the degree of degradation to be quantitatively determined, thereby enabling the abnormality or degradation state of the motor 12 to be accurately detected. For example, an abnormality caused by minute foreign matter entering the gap between the rotating and stationary parts of the compressor 1 can be quantitatively detected as the abnormal power energy Psgh, thereby allowing the presence or absence of an abnormality and the degree of degradation of the compressor 1 to be quantitatively determined.

[0083] According to the first embodiment, when a phenomenon that mechanically deteriorates the compressor 1 occurs, a value indicating the deterioration or abnormality can be quantitatively detected as the abnormal power amount Psgh, and therefore the degree of deterioration can be diagnosed. Examples of phenomena that mechanically deteriorate the compressor 1 include metal wear due to metal contact between the main shaft 45 of the motor 12 and the sliding bearing, and foreign matter that has entered the compression mechanism of the compressor 1 becoming caught.

[0084] From the viewpoint of maintaining a system equipped with the compressor 1, it is important to know the progression of the abnormal state of the compressor 1, i.e., the degree of deterioration of the compressor 1, in order to recognize the urgency of maintenance. The motor current alone is not sufficient as a physical quantity that indicates the amount of mechanical damage inside the compressor 1. Conventional methods have had the problem of being unable to estimate the progression of the deterioration of the compressor 1. In contrast, according to the first embodiment, the deterioration state of the compressor 1 can be quantitatively estimated by using a value obtained by integrating the abnormal power component Psg over time as a physical quantity that indicates the deterioration of the compressor 1.

[0085] Embodiment 2. In Embodiment 1, the case where the power of the motor 12 is used as an index value indicating an abnormality in the motor 12 is described, but in Embodiment 2, the mechanical power of the motor 12 is used as an index value indicating an abnormality in the motor 12. In Embodiment 2, the same components as those described in Embodiment 1 are assigned the same reference numerals, and detailed descriptions thereof will be omitted. Furthermore, in Embodiment 2, detailed descriptions of the components and operations described in Embodiment 1 will be omitted.

[0086] The configuration of the motor drive device of Embodiment 2 will be described. Fig. 13 is a functional block diagram showing an example of the configuration of a controller provided in the motor drive device according to Embodiment 2. Controller 23 shown in Fig. 13 is provided in motor drive device 15 of refrigeration cycle apparatus 100 shown in Fig. 1.

[0087] 13 , the controller 23 includes a voltage command calculation means 24 and an abnormality index value extraction means 25 b. The abnormality index value extraction means 25 b receives the speed command value ω* from the control device 8, the phase θ indicating the estimated position of the rotor 44 from the position / speed estimator 34, and the d-axis current Id and the q-axis current Iq from the second coordinate converter 33. The abnormality index value extraction means 25 b calculates the abnormal work based on the d-axis current Id, the q-axis current Iq, and the phase θ.

[0088] Fig. 14 is a functional block diagram of the abnormality index value extraction means shown in Fig. 13. The abnormality index value extraction means 25b has an index value calculation means 60a, a filter means 61, and an integrating means 62. The index value calculation means 60a calculates the power W of the motor 12 as follows. First, the index value calculation means 60a calculates an estimated value τe of the output torque using the following equation (1):

[0089] τe=(Ld×Id+Φf)×Iq−Lq×Iq×Id...(1) τm=Pp×τe...(2) Δθm=Δθ / Pp...(3)

[0090] In equation (1), Φf is the magnetic flux of the permanent magnet of the motor 12, Ld is the d-axis inductance, and Lq is the q-axis inductance. The index value calculation means 60a stores the values ​​of Φf, Ld, and Lq in advance. The output torque τe shown in equation (1) is a physical quantity called electrical torque, which corresponds to the electrical frequency and electrical phase of the inverter output. If the mechanical torque is τm, the relationship between the mechanical torque τm and the electrical torque τe is expressed as shown in equation (2) using the number of pole pairs Pp of the motor. In the second embodiment, the power W is calculated using an electrical physical quantity, but the power W may also be calculated using a mechanical physical quantity. In this case, the mechanical rotation angle Δθm is calculated based on equation (3), and the power W is obtained by multiplying the mechanical rotation angle Δθm by the mechanical torque τm.

[0091] The index value calculation means 60a also calculates an estimated value Δθ of the rotation angle, which is the amount of change between the phase θ indicating the estimated position received the previous time the power W was calculated and the phase θ indicating the estimated position received this time when the power W is calculated. The index value calculation means 60a then calculates the product of the estimated value τe of the output torque and the estimated value Δθ of the rotation angle to calculate the power W.

[0092] The filter means 61 performs filtering to remove components that represent normal operating conditions of the compressor 1 from the power W, thereby extracting an abnormal power component Wsg. The filter means 61 transmits the abnormal power component Wsg to the integrator means 62. When the integrator means 62 receives the abnormal power component Wsg from the filter means 61, it performs time integration on the power component Wsg to calculate the abnormal work Wsgh. The integrator means 62 transmits abnormal information Wir, which is information indicating the abnormal work Wsgh, to the diagnostic means 35 at regular intervals.

[0093] The operation of motor drive device 15 in the second embodiment is the same as the operation procedure described with reference to FIG. 10 except for the type of abnormality index value, and therefore detailed description thereof will be omitted.

[0094] According to this embodiment 2, the abnormality index value extraction means 25b calculates the abnormal work Wsgh of the motor 12, so that the user and maintenance manager of the refrigeration cycle device 100 can estimate not only whether or not there is an abnormality in the motor 12 or the compressor 1, but also whether or not there is mechanical deterioration of the compressor 1.

[0095] In the above-described first and second embodiments, the diagnosis means 35 is provided in the remote controller 9, but the electronic device in which the diagnosis means 35 is provided is not limited to the remote controller 9. The diagnosis means 35 may be provided in the control device 8 shown in Fig. 1 . Furthermore, the diagnosis means 35 may be provided in a device separate from the refrigeration cycle apparatus 100.

[0096] (Modification 1) Modification 1 is a refrigeration cycle system having the refrigeration cycle apparatus 100 of Embodiment 1 or 2. Fig. 15 is a diagram showing a configuration example of a refrigeration cycle system according to Modification 1. In Modification 1, the refrigeration cycle apparatus 100 will be described as being the refrigeration cycle apparatus 100 of Embodiment 1, but the refrigeration cycle apparatus 100 may be the refrigeration cycle apparatus 100 of Embodiment 2.

[0097] As shown in Fig. 15 , a diagnostic means 35 is provided in an information processing terminal 17 connected to a network 18. The network 18 is, for example, the Internet. The information processing terminal 17 is, for example, an information processing device such as a smartphone or a tablet terminal. The information processing terminal 17 is carried by a user or maintenance manager of the refrigeration cycle apparatus 100. The information processing terminal 17 has a diagnostic means 35, a communication means 36 for connecting the diagnostic means 35 to the network 18, and a display means 37. The display means 37 is, for example, a liquid crystal display. The diagnostic means 35 is provided in a controller not shown in the figure.

[0098] The controller 23 has a communication means 26 for communicating with the information processing terminal 17 via the network 18. The communication means 26 transmits information received from the diagnosis means 35 via the communication means 26 and the communication means 36 to the voltage command calculation means 24. The communication means 26 and the communication means 36 are communication circuits that transmit and receive data to and from each other in accordance with, for example, the IP (Internet Protocol) communication standard.

[0099] In the refrigeration cycle system of Modified Example 1, an operation different from that described in Embodiment 1 will be described. When the abnormal power amount Psgh is greater than the first threshold value th1, the diagnostic means 35 determines whether the amount of change in the abnormal power amount Psgh is greater than the second threshold value th2. If the result of the determination is that the amount of change in the abnormal power amount Psgh is greater than the second threshold value th2, the diagnostic means 35 transmits information to the communication means 26 via the communication means 36 to indicate that the upper limit value of the operating frequency of the compressor 1 will be reduced. When the communication means 26 receives the information to indicate that the upper limit value of the operating frequency of the compressor 1 will be reduced from the information processing terminal 17, the communication means 26 transfers the information to indicate that the upper limit value of the operating frequency of the compressor 1 will be reduced to the voltage command calculation means 24.

[0100] When the voltage command calculation means 24 receives information from the diagnosis means 35 via the communication means 26 to lower the upper limit of the operating frequency of the compressor 1, the voltage command calculation means 24 sets the upper limit of the operating frequency of the compressor 1 to a value smaller than a predetermined maximum value. This makes it possible to suppress the progression of deterioration of the compressor 1 when an abnormality occurs in the motor 12 or the compressor 1, and to prevent the operation of the refrigeration cycle apparatus 100 from stopping before a maintenance manager can perform maintenance on the compressor 1.

[0101] According to this variant example 1, the diagnostic means 35 remotely monitors the deterioration state of the motor 12 or the compressor 1 via the communication means 36 from a device other than the refrigeration cycle device 100, thereby reducing the number of regular maintenance tasks for the compressor 1 and reducing the human burden of maintenance.

[0102] In the above-described first embodiment, second embodiment, and first modification, the integrating means 62 is provided in the motor drive device 15 of the refrigeration cycle apparatus 100, but this is not limited to this. The integrating means 62 may be provided in a device separate from the refrigeration cycle apparatus 100, similar to the diagnosis means 35. For example, the integrating means 62 may be provided in the information processing terminal 17 shown in Fig. 15. In this case, the calculation processing load on the controller 23 is reduced.

[0103] REFERENCE SIGNS LIST 1 Compressor, 2 Heat source side heat exchanger, 3 Throttle device, 4 Load side heat exchanger, 5 Four-way valve, 6 Accumulator, 7 Refrigerant piping, 8 Control device, 9 Remote controller, 10 Refrigerant circuit, 12 Motor, 13 DC voltage source, 15 Motor drive device, 17 Information processing terminal, 18 Network, 20 Inverter, 21 Power converter, 22 Current sensor, 23 Controller, 24 Voltage command calculation means, 25, 25a, 25b Abnormality index value extraction means, 26 Communication means, 30 Speed ​​control section, 31 Current control section, 32 First coordinate conversion section, 33 Second coordinate conversion section, 34 Position speed estimation section, 35 Diagnosis means, 36 Communication means, 37 Display means, 40 Fixed scroll, 41 Swinging scroll, 42 Power supply terminal, 43 Stator, 44 Rotor, 45 Main shaft, 46 Main shaft eccentric portion, 47 suction pipe, 48 discharge port, 49 discharge pipe, 50 main bearing, 51 auxiliary bearing, 52 sealed container, 54 oil pump, 60, 60a index value calculation means, 61 filter means, 62 integrating means, 63 low pass filter, 64 high pass filter, 71a to 73a, 71b to 73b switching elements, 75 operation unit, 76 display unit, 77 control unit, 80 processing circuit, 81 processor, 82 memory, 83 bus, 100 refrigeration cycle device, 101 heat source side unit, 102 load side unit.

Claims

1. A motor drive device that performs feedback control of a motor based on a motor current, which is the current flowing through the motor, comprising: index value calculation means that calculates the power or power of the motor as an index value for determining whether or not there is an abnormality in the motor, based on the motor current and control parameters used for the feedback control; filter means that performs filtering processing to remove components of a normal operating state from the index value calculated by the index value calculation means and extract abnormal components; and diagnosis means that diagnoses abnormalities or deterioration of the motor based on the abnormal component of the index value.

2. A motor drive device as described in claim 1, further comprising an integrating means for time-integrating the abnormal component of the index value, and wherein the diagnosing means diagnoses abnormalities or deterioration of the motor based on one or both of the abnormal component of the index value and the integral value of the calculation result by the integrating means.

3. A motor drive device according to claim 1 or 2, further comprising an inverter that supplies power to the motor, wherein the index value calculation means calculates the power of the motor by calculating the inner product of the motor current and a voltage command value that is the control parameter input to the inverter.

4. A motor drive device according to claim 1 or 2, further comprising an inverter that supplies power to the motor, wherein the index value calculation means calculates an estimated value of the torque of the motor using a predetermined equation that includes the motor current, calculates an estimated value of the rotation angle of the motor from the motor current and an amount of change in an estimated position of the rotor of the motor that is based on a voltage command value that is the control parameter input to the inverter, and calculates the power by calculating the product of the estimated value of the torque and the estimated value of the rotation angle.

5. A motor drive device according to any one of claims 1 to 4, wherein the filter means comprises: a low-pass filter that removes harmonic components having a fundamental wave corresponding to the rotational frequency of the motor in a normal operating state from the index value; and a high-pass filter that removes low-frequency components of the motor in a normal operating state from the index value.

6. The motor drive device according to claim 5, wherein the filter means removes a change in a speed command value for the motor from the index value.

7. The motor drive device according to any one of claims 1 to 6, wherein the load of the motor is a compressor, the rotating shaft of the motor being supported by a sliding bearing, and the diagnostic means outputs the diagnostic results to the outside.

8. A refrigeration cycle device comprising: a refrigerant circuit including a compressor equipped with a motor; and a motor drive device according to any one of claims 1 to 7 that drives the motor.

9. A refrigeration cycle system comprising: a refrigerant circuit having a compressor equipped with a motor; a power converter having an inverter that supplies power to the motor; a voltage command calculation means that performs feedback control of the motor via the inverter based on a motor current that is a current flowing through the motor; an index value calculation means that calculates the power or power of the motor as an index value for determining whether or not there is an abnormality in the motor based on the motor current and a control parameter used for the feedback control; a filter means that performs filtering processing to remove normal operating state components from the index value calculated by the index value calculation means and extract abnormal components; and a diagnosis means that diagnoses abnormalities or deterioration of the motor based on the abnormal component of the index value.

10. A refrigeration cycle system as described in claim 9, further comprising a display means connected to the diagnostic means, wherein the diagnostic means determines whether the value of the abnormal component is greater than a predetermined abnormality determination threshold, and if the value of the abnormal component is greater than the abnormality determination threshold, causes the display means to display information that an abnormality has occurred in the motor or that the motor is deteriorated.

11. A refrigeration cycle system as described in claim 9, comprising: an integrating means for integrating the abnormal component of the index value over time; and a display means connected to the diagnosing means, wherein the diagnosing means, when the integrated value calculated by the integrating means is greater than a predetermined first threshold, determines whether or not a change in the integrated value is greater than a predetermined second threshold, and, when the change is greater than the second threshold, causes the display means to display information that the integrated value has exceeded the second threshold.

12. The refrigeration cycle system according to claim 11, wherein the diagnostic means transmits information to the voltage command calculation means to lower the upper limit of the operating frequency of the compressor when the amount of change is greater than the second threshold value.

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